Update exception statement

Signed-off-by: Divya Madala <divyaasm@amazon.com>

Author: Divyaasm

src/validation_workflow/validation_args.py

@@ -146,7 +146,7 @@ def __init__(self) -> None:
 
         if args.distribution == "docker":
             if args.osd_build_number != "latest" and "opensearch-dashboards" not in args.projects:
-                raise Exception("osd_build_number argument cannot be provided without specifying opensearch-dashboards in --projects")
+                raise Exception("--osd_build_number argument cannot be provided without specifying opensearch-dashboards in --projects")
             if not(args.validate_digest_only) and not(args.using_staging_artifact_only):
                 raise Exception("Provide either of --validate-digest-only and --using-staging-artifact-only for Docker Validation")